The present invention relates to automobiles with an altitude compensated fuel feed means, such as an altitude compensated carburetor.
An automobile having an internal combustion engine with an altitude compensated fuel feed means is known. With the altitude compensated fuel feed means air fuel mixture will be prevented from becoming excessively rich when the automobile is operating at high altitudes.
If a fuel feed means is set to provide an optimum air fuel ratio at low altitudes, the air fuel ratio will become considerably richer as altitude increases because air density decreases.
Various kinds of altitude compensation systems employing an aneroid bellows have been proposed and put into practice in order to solve the above described problem. Among them, it is well known to provide a carburetor with an independent additional air supply passage and with an aneroid bellows actuated valve. The valve will increase the flow sectional area of the additional air supply passage as altitude increases to prevent enrichment of the mixture fed to an engine from the carburetor. The problem encountered in the altitude compensation system employing an aneroid bellows resides in the use of such aneroid bellows. It has often been experienced that the aneroid bellows is damaged due to the vehicle vibration. Moreover the bellows is expensive and thus has a cost disadvantage. It has also been experienced that the vehicle vibration is apt to wear a valve at a fast rate so that precise control of the amount of air entering into the carburetor cannot be expected after a long use.